Extractors that use a liquid to clean a carpet, upholstery, or like surface are well known in the art. A conventional extractor generally includes a cleaning liquid or diluted detergent delivery system including a container for holding the cleaning liquid, a rotating agitator or a revolving scrubber for scrubbing the surface to be cleaned, and a gravity feed or pump for delivering the cleaning liquid to the surface. The conventional extractor also includes a cleaning liquid recovery system having a recovery nozzle, a suction generating device, such as a motor driven fan, and a dirty cleaning liquid recovery tank. Such extractors are more effective than typical vacuum cleaners due to their ability to loosen ground in dirt by the action of the rotating agitator or scrubbing brush in conjunction with application of the cleaning liquid.
A rotating agitator of an extractor is effective in loosening dirt on the surface of a carpet pile. However, such agitators are not as effective in removing particles embedded deeply in the carpet. Also, rotating agitators tend to push dirt particles down into the carpet, thereby making it more difficult to effectively clean the carpet. Accordingly, there is a need for an agitator construction for an extractor that can provide a more through cleaning action.